All this talk of "over-cooling" the engine has me wondering. We regularly talk about temps in the 200-250 range as normal, expected, and good. On my sedan, if the temp goes above 190, it's unhappy. Why such a dramatic difference? Thanks for any and all enlightenment.

Did the Daves Mods w/Big Gun exhaust, K&N filter on an '08 650. Live in Denver. Jets-M-155, P-55, I have a little stumble when i take off from idle. rode it 70 miles today, and plug looks exactly like when i cleaned it before ride, not white, not black, not even wet.... So, which jets do i need to order to get rid of the hesitation off idle...! Carbs are not my Forte...!

I recently bought an XR650L (Oct of 2011) and finally had the chance to get out and ride. I have spent the last week in the Prescott, Az area riding trails, I'm having a great time and will try to make a few mods over the next month or two!
-AK

The main reason Barrons motor failed was he didn't have the oil pumps metal oil line in the oil pump sockets all the way and the line was sticking up to high and the oil pump drive gear rubbed a hole through it..

That explains way the motor went 400 miles and then failed, the gear was rubbing against the line until it rubbed a hole through it and puffffff....... I know it's not funny but all you guys need to make sure the line is seated in the sockets properly and the o-rings are good also so it doesn't happen to you.
I also found the crank seal was pinched and the o-ring was missing between the case and pump.

I have a picture of the hole in the line if someone wants to post a picture for me...

Thanks for the autopsy report. Damn interesting. I can post the pic.

I just replaced the clutch in the 600R over the weekend and there's that little nub and o'ring that goes from the side cover to the oil pump... hope it didn't fall out when I was putting the cover back on.

This is why you can't be in a rush when you're putting an engine together...

Below is a pic of the internal oil line from my oil pump, where I did not get the line in all the way which allowed the oil pump gear to chew it's way through the line. FWIW, there was no external "out of the blue" noise.... until the engine died of course....

Thanks again for all your help CW.

-Barron

__________________1996 XR650L with a couple mods
If everyone brewed beer there would be no war.

+1 on EBC sintered and Galfer. I have run both and had excellent results on my moto bike and the pig. Sintered pads work well when they get warm. Luckily, the pig has a lot of kinetic energy and quickly heats them to operating temp. If you were poking along on a trail and just using compression braking I would go with the non-sintered Galfer. My next pads will be these:

They will be used with my crfstuff conversion. If any of you with a Honda based USD conversion want more braking, I highly recommend the CRF stuff set up. That and the ball and socket '08+ master cylinder make for one smooth powerful set up. When Wattner did his build I recommended this to him and I think he and CW were both impressed with the quality of the CRF Stuff kit. Four years ago when I purchased this oversize kit I got it off ebay after a phone call with the owner, Scott Hart and was suitably impressed. Somehow he got a copy of an HRC rotor and then set out to improve it. Now a few years after he started tinkering he supplies the Honda Factory team with brake set ups. Good write up on his site on how to properly bed the pads.

I recently bought an XR650L (Oct of 2011) and finally had the chance to get out and ride. I have spent the last week in the Prescott, Az area riding trails, I'm having a great time and will try to make a few mods over the next month or two!
-AK

Welcome! I see you have the skid plate, tank and tank vent hose already modded. Next is Dave's mods and if you ride off road dropping the countershaft to a 14 tooth XR650R countershaft sprocket. This will save countershaft from premature death and give you a little more grunt. Happy trails mate!

I recently bought an XR650L (Oct of 2011) and finally had the chance to get out and ride. I have spent the last week in the Prescott, Az area riding trails, I'm having a great time and will try to make a few mods over the next month or two!
-AK

Thanks for the sweatshirts, a little small though. The floral print smock is nice, but I'm really more of a winter.

To get the motors potential buy the HSR48, I've done all the testing on my bike at first I tried the stock carb which worked fine but was lacking topend so I went to a FCR41 thinking the stock carb was junk it ran great on the bottom and mid but same problem no top...
So then I tried a HSR42 and gained 14 mph by 1mm larger throat body size so I was on to something..
Tried a HSR45 and then a HSR48 and gained 25mph with the 45mm and 40mph with the 48mm carb and it still needs more carb like a 52mm....

What you can do is bore an FCR41 to a 45mm and it's a bolt on or just get it over and buy a HSR48mm and be done with it.

All this talk of "over-cooling" the engine has me wondering. We regularly talk about temps in the 200-250 range as normal, expected, and good. On my sedan, if the temp goes above 190, it's unhappy. Why such a dramatic difference? Thanks for any and all enlightenment.

To get the motors potential buy the HSR48, I've done all the testing on my bike at first I tried the stock carb which worked fine but was lacking topend so I went to a FCR41 thinking the stock carb was junk it ran great on the bottom and mid but same problem no top...
So then I tried a HSR42 and gained 14 mph by 1mm larger throat body size so I was on to something..
Tried a HSR45 and then a HSR48 and gained 25mph with the 45mm and 40mph with the 48mm carb and it still needs more carb like a 52mm....

What you can do is bore an FCR41 to a 45mm and it's a bolt on or just get it over and buy a HSR48mm and be done with it.

What affect if any did the larger than 41 have on the bottom. I am running the FCR41 and am very happy with its performance. But I am not looking for more top end speed.